Alternating-current motor.



PATENTE'D JULY 23, 1907.

E. F. W. ALEXANDERSON. ALTERNATING CURRENT MOTOR.

APPLIOATION FILED D30. 10, 1906,

Ernsr F.W.Ak; anderson.

UN ITED P STATES PATENT OFFICE.

ERNST F. W. AL *XANDERSON, Oi SOHENECTADY, NEW YORK, ASSIGNOR TO GENERAL ELECTRIC COMPXOTY, A UORPORATlON OF NEW rZORK.

No. ashore.

To all "whom it may concern.

Be it known that I, ERNST F. W. ALLXANDnRsN, a subject oi the King of Norway and Sweden, residing at Schenectady, in the county of. Schenectady, State of New York, have invented certain new and useful Improvements in Alternating-Current Motors, oi which the following is a specification.

My invention relates to dynamo-electric machines of the commutator type, emjiloying high resistance-leads for the purpose of improving commutation, and is particularly applicable to alternating-current motors o! the commutator type.

The object of my invention is to arrange the leads in such manner that the heat produced in these leads, particularly at starting, be effectively conducted away; thereby making it possible to employ leads oi comparatively cross-section.

My invention in its broadest aspect consists in arranging the leads in the some slots with the coils and placing each lead close to a conductor one of the coils in the slot and separated from the conductor only by a thin strip of insulation. A portion of the heat generated in the lead is transferred through the thin strip of insulation to the coil conduetorf'so as to reduce the temperature or the lead. It the lead is placed close to one of the conductors or" the coil to which it is con nected, so that the lead and conductor are in close mutually inductive relation, the voltage between the lead and conductor at any time is only that due to the.

them may be very thin. I further increase conduction of heat from the leadoy iorming both the lead and the conductor of thin st ips, so that they present to invention; and Fig. 2 shows a cross-sectional view of the coil-conductors and leads in a slot.

In Fig. 1, A represents the slotted armature core, B the coils carried in the slots, 0 the commutator, D the commutator brush, and E the high-resistance leads which are of a suitable high-resistance material and are connected to the coils on the side of the armature away from the commutator. The coils B are shown in heavy lines; the conductors which are in the top of 'the slots, being shown in full lines, and the conduc- Specification of Letters Patent.

Application filed December 10, 1%6. Serial 1%.

Patented July 23, 1907.

in the form of narrow strips. The leads are interleaved with the conductors and each lead is separated from a conductor of the coil to which it is connected only by a thin strip of insulation. As has been above explained, this insulation need be only sufiicient in thick ness to resist the voltage due to the ohmic drop in the conductor of the coil and in the lead, since lead and conductor are inclosc mutual relation, as Fig. 1. a

.lllrat i claim as new and desire to secure by Letters Patent oi the United States, is,- V

1. In :1 dynamo-electric machine, a slotted armature, coils carrled in the slots, :1 commutator, and high-resist once leads carried in the slots and connecting the cells to shown in the commutator, each. lehdbeing arrnnged'close to a conductor of one of the coils and separated therefrom only by a thin strip of insulation.

2. In a' dynamo-electric machine, a slotted armature, coils curried in the slots, :1 commutator, and hlgh-reslstonce leads counectlng the coils to the commutator-and in -terleave l with the coil-conductors in the bottom 01: the

slots, each lead bcln separated from a coll conductor only by a thin strip of insulation.

3. ln 2. dynamo-electric machine, :1 slotted armature, coils carried in the slots, :1 commutator, highreslstance le carried in the'slots and connecting the coils to the cc of the-coil to whi ch it ,is connected and'soparated there from. only o a thin strip of insulation. v

s. in dynamo-electric machine, a slotted armature.

unce leads connecting the coils to the commutator and interleaved with the coil-conductors in the bottom of the slots, each lead being separated from a conductor of the coll to which lotion.

nmutotor, each lead being arranged close to a conductor it is connected only by :1 thin strip of insucells carried in slots, :1 commutator, and high reslsb.

5. In a dynamo -electrlc machine, a slotted nrmature, I colls cmrled in the slots, 11 commutator, hlgh-reslstnnce lends carried in the slots and connecting the coils m thecommutator, each lead and a conductor of each coll being in the form of thin conducting str'iis and the two being separated "by only u fill-n strip of insulation.

6. In a dynamo-electric machlne, a slotted armature, cells 'cnrrled in the slots, 11 commutator, higlrreslstance ads connectlng the cells to the commutator and Intelleoved with the coll-conductors 1n the bottom of the slots, each lead and a conductor of each coll being in the form of thin conductlng strlps and the two being separated by only a thin strip of insulation.

7. In a dynumo-electrlc machine, a slotted armature,

coils carried in the slots, :1 commutator, hlghmcslstance I leads carried in the slots and connecting the coils to the. commutator, each lead being arranged close to a conductor .of-the coil to whichit is connected and separated there- 5 from only by a thin strip of insulation, both the lead and the conductor being in the form of thin conducting strips. In a dynamo-electric machine, a slotted armature, ,-colls carried in the slots, :1 commutator, and high-resist- Qmce leads connecting the coils to the commutator and -in- 1 TD terleaved with the coil-conductors in the bottom of the slots, each lead being separated from a conductor of the coil to which it is connected only by a thin strip of insulotion, both the lead and the conductor being in the form of thin conducting strips.

In witness whereof, I have hereunto set my hand this 15 8th day of December, 1906.

ERNST F. W. ALEXANDERSON. Witnesses:

BENJAMIN B. HULL, HELEN ORFORD. 

